uart.h

Go to the documentation of this file.

/*
 * uartavr interrupt driven serial communication for 8bit avrs
 * Copyright © 2016 Christian Rapp
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the organization nor the
 * names of its contributors may be used to endorse or promote products
 * derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY ''AS IS'' AND ANY  EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL yourname BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef UART_H
#define UART_H

/*
 * Make sure we have defined F_CPU before we include anything. This is very
 * important and you must change this value according to your needs. The easiest
 * way to do this is to use this in a Makefile
 * -DF_CPU=1000000
 */
#ifndef F_CPU
#define F_CPU 16000000UL /* 16MHz µc */
#endif                   /* ifndef F_CPU */
#ifndef BAUD
#define BAUD 9600L
#endif /* ifndef BAUD */

/*
 * Some basic includes
 */
#include <inttypes.h>
#include <stdlib.h>
#ifdef PRINTF
#include <stdio.h>
#endif

#include <avr/io.h>
#include <util/atomic.h>
#include <util/setbaud.h>

#define UARTAVR_VERSION_MAJOR 0

#define UARTAVR_VERSION_MINOR 3

#define UARTAVR_VERSION_PATCH 0

#define CR "\n\r"

#define CR_PRINTF "\r"

#define BUFFSIZE 64

struct DirBuff {
    char buff[BUFFSIZE];       
    char *start_ptr;           
    char *end_ptr;             
    char *inpos_ptr;           
    char *outpos_ptr;          
    size_t items;              
    uint8_t full;              
    void (*rx_callback)(void); 
    void (*tx_callback)(void); 
    void (*buff_empty)(void);  
};

enum DIR_BUFFS {
    RX_BUFF, 
    TX_BUFF  
};

struct CBuffer {
    struct DirBuff rx_buff; 
    struct DirBuff tx_buff; 
} cb;                       
/* TODO: I am not sure if this instance of CBuffer needs to be volatile. But if I
*  do this I get lots of compiler warnings.
*/

struct UARTcfg {
    uint8_t tx; 
    uint8_t rx; 
    void (*rx_callback)(void); 
    void (*tx_callback)(void); 
    void (*buff_empty)(void);  
};

void cb_init(void);

void get_direction_buffer(enum DIR_BUFFS dir, struct DirBuff **dbuff);

uint8_t cb_pop(char *c, enum DIR_BUFFS dir);
uint8_t cp_push(char c, enum DIR_BUFFS dir);

void init_uart_cfg(struct UARTcfg *cfg);

void init_UART(const struct UARTcfg *cfg);

#ifdef LIB_DEBUG
void put_noi_UART(char c);
void puts_noi_UART(const char *s);
#endif /* LIB_DEBUG */

void put_UART(const char c);

void puts_UART(const char *s);

uint8_t get_UART(char *s);
uint8_t gets_UART(char *s);

#ifdef PRINTF

int puts_printf_UART(char c, FILE *stream);
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-variable"

static FILE uartavr_stdout =
    FDEV_SETUP_STREAM(puts_printf_UART, NULL, _FDEV_SETUP_WRITE);
#pragma GCC diagnostic pop
#endif

#endif /* ifndef UART_H */